Mark Schubert, head coach to aquatic superpower the USA, is a man who knows his job: to produce the fastest swim team in the world.

In the midst of all the confusion, doubt and denial over the LZR Racer, Schubert says this: 'My advice to athletes is 'you have a black and white decision - the money or the gold medal'. And it's going to be a real test of character as to what choice they make. There is no doubt the suit makes a difference and there is no doubt that there is one manufacturer that's put millions into research while the other manufacturers are more into fashion. If you take best times of world record holders and their new times, the difference is 2 per cent. Nobody at this level [world-class athletes] can afford to give up 2 per cent. It is not rocket science.'

In one way, of course, it is rocket science: technology developed by NASA, the space agency that worked with Speedo on the suit's evolution, is used to bond the panels on the world's first seamless suit. If that has helped to produce a smoother more streamlined garment, the big breakthrough has been in compression and the positioning of support panels around the girdle that provide a level of core stability for swimmers never present before. Swimmers emerge from races in which they have out-performed themselves with tales of 'the tightest suit I've ever worn'.

The customary fatigue in legs and abdominal muscles is minimal. 'I have massive legs but and that can weigh heavy at the end of a race, but with this suit, I don't feel that effect at all,' said Rachel Komisarz, and American sprinter in Manchester. Her teammate Ryan Lochte, in line to be the star of the show here with several gold medal chances, added: 'It feels like I'm floating, like I'm swimming downhill.'

This is NOT about buoyancy. It is about core stability, the binding of the body from three parts into one, the propping up of legs, the aid provided to soft tissues that hold back performance. That is what swimmers mean by floating. The USA team, many members of which helped to develop the suit, has embraced the new technology wholeheartedly, the swimmers and coaches happy to admit to the advantage that the suit clearly brings. British swimmers have been more reluctant, some because of contractual obligations, others because they have still to catch up with the notion that the suit is significant.

Schubert has told the USA team that they need to think medals not money. He also had a message for Speedo's rivals as they head to a meeting on Saturday in Manchester with FINA, the international governing body, to discuss the Lausanne-based federation's process of suit approval. 'The other manufacturers need to put the effort in, catch up and quit whining,' said Schubert.

'The fact is that there is nothing more important than having the manufacturers be competitive because they do provide the living for the athletes and that's what's really helped the sport of swimming to allow the athletes to swim to older ages, more like track and field. I have always felt that swimming should be like track and field (in terms of the ages and longevity of athletes) but the problem we have now is that everyone is contracted to one suit and some are contracted to an inferior product and those manufacturers need to let go and everyone can compete on a level playing field with a product that is the same and then they need to put the effort in and catch up.'

Schubert added: 'I think really the latest three generations of suits have had a great effect. I'm very excited about the technology. I think its another exciting aspect of this sport. I've been excited about this suit since Melbourne because the day after Melbourne I went to Canberra to watch Michael Phelps, Ryan Lochte, Natalie Coughlin, Kate Ziegler and Katie Hoff and watched them do eight hours of testing with the new suit, so I've been heavily involved in the process, the observation ... Speedo been working with athletes and getting feedback from them, asking them how they feel. It's very important to get that input from the people who have to wear the suit, telling the manufacturers how they felt about the suit and how it helps and how it doesn't help.'

It's the kind of work he recommends to Speedo's rivals when they manage to 'catch up', which may not come in time for the Olympic Games. Schubert says: 'I don't see any way that they can do it by Beijing but certainly within the next year they can make vast improvements.'

Schubert has been at the cutting edge of finding the next answer throughout his coaching career, one that was loaded with the challenges of the GDR years and onset of the professional era. How now will the USA respond to the latest wave of world-record setting performances and gains across the board in many nations? 'Melbourne was great for the USA. We had a meeting of our best coaches in December and we told them 'expect unbelievable times from other nations this spring but don't be intimidated by that - the rest of the world is going to set a much higher bar'. We anticipated it and we've challenged our coaches to take that high bar down. What's kind of fun with us not having our trials 'til June is that we'll see where the bar is and then the challenge is ours.'

He added: 'We had a wonderful experience in Melbourne, without a doubt. But we're realistic enough to know that the challenge is going to come from many other nations and we'll be ready for those challenges. I think we'll be competitive in every event, its going to be a fabulous Olympic Games.'

Part of Schubert's work is to get on the national swim hotline and instill in his coaches and swimmers a sense of belonging in a programme that is always at the leading edge. What Phelps and Bowman do today is known by key people across the US tomorrow. It inspires and instructs. Who else is held out as a force to follow? 'Eddie Reese, he's got three world record holders, Terri McKeever working with Natalie Coughlin, and what's going on in the culture of North Baltimore, the best club programme in America. It produced Michael Phelps, now Katie Hoff. Maybe two of the best swimmers ever. Its exciting for the rest of the coaches to learn from those kind of cultures.' And success begat success, generation after generation.

What separates the past from the present? 'The difference in our present generation of American swimmer is that, because of the professional era, the better swimmers stay in longer, are more mature and they come to this level of competitiveness not just more physically ready but more emotionally ready and I think that's made a huge difference.' Moving the sport more in line with traditions seen in track and field presents its challenges. 'Our challenge as a nation is that we need to prepare the next generation of swimmers for when this generation of swimmers retires,' says Schubert. 'That's a tough challenge'. The new crew will face something of a baptism of fire: lack of exposure to international competition is not to be recommended. The USA and Australia, two nations whose success exacerbates the challenge, are working on it, apart and together. 'We have an initiative over the next quadrennial to generate more opportunities for those young athletes. We're talking with Australia about that because Alan Thompson (head coach to the Dolphins) kind of sees the same challenge and I think the Australia men's team faced that when Thorpe retired and are looking now at the retirement of Grant Hackett.'

It's a problem the world wishes it had. Schubert smiles.

Another problem is Eamon Sullivan's 21.28. Had he analysed it and did he know what he was seeing, was there something that explained the speed? 'It was spectacular. I've analysed the swim, I've seen the film but you know there's nothing like seeing it in the person and I so look forward to it. I think I'll be able to answer that question better when I see it live.' The fascinating aspect of the sprint fight is the different dimensions of the fighters: Bernard the Bulk versus Sullivan the Stick, both capable of very similar performances on the clock but so very different as they line up on the blocks and different again when the speed takes them. 'It's kind of the beauty of the sport. You have tiny guys and giant guys and sometimes when you dive into the water it kind of equals it out somehow. It's fabulous,' said Schubert, the impossible sound of a bumble bee in his brain.